Liquid tight prismatic container of paper, cardboard or the like



y 1965 G. MEYER-JAGENBERG 3,

LIQUID TIGHT PRISMATIC CONTAINER OF PAPER, CARDBOARD OR THE LIKE Filed Sept. 13, 1963 2 Sheets-Sheet 1 y 27, 1955 G. MEYER-JAGEN RG 3,197,112

LIQUID TIGHT PRISMA CONTAI PAPER, CARDBOARD THE LI 2 Sheets-Sheet 2 Filed Sept. 13, 1965 man I g.

United States Patent The present invention relates to liquid tight containers of prismatic or polygonal form, fabricated from paper, cardboard or like carton-forming materials, and more particularly relates to a container, the tubular shaped body of which is closed by means of upper and lower roof-like folding closures with inwardly folded gable surfaces.

Containers of paper, cardboard and the like are being used increasingly in the packaging of mass consumption goods, such as milk and other liquid or solid foodstuffs,

due to the fact that such containers can be discarded after the contents have been consumed, thereby eliminating the return of the empty containers. An essential condi tion for permitting such so-called single use containers to be feasible economically is a low cost, as regards the materials used and rational production procedures. More particularly, the total cost of such containers must be in a ratio which is economically possible asto the value of the goods to be introduced into the containers, in order that an increase in the sale price by virtue of such container costs can be avoided.

Paper preferably coated on one side or face with a thermoplastic synthetic material has demonstrated to be particularly suitable for the manufacture of such containers where such coatings possess impregnating properties as well as adhesive properties when subjected to pressure and heat. Generally, the manufacture of such containers comprises providing a fiat blank with score or fold lines, and by means of folding and adhesion of the longi tudinal seam form a flat tubular container body. Subsequently the tubular body is erected to its full cross-sectional shape, and is provided at its lower end with a roof-like folding closure with inwardly folded gable surfaces. After the container has been filled, the upper end thereof is also closed by a roof-like folding closure with inwardly folded gable surfaces.

In view of the savings in material costs, thinner paper is preferably employed, but such paper, however, does possess certain disadvantages. More specifically, the side walls of a filled container have a tendency, due to the pressure of the liquid, to bulge outwardly, and in addition, the rigidity of the entire container is somewhat impaired by such thin paper. In the employment of such thin materials, certain-measures'must be taken which, in spite of the inherent, low rigidity of the material will impart to the container an adequate rigidity and resistance capacity. For the above reasons, provision has been made for providing outwardly directed and positioned longitudinal seams by internal adhesion or sealing of the Walls of the container, whereby due to the sealing of layer up on layer the cut edges cannot come into contact with the liquid contents of the container.

Aside from the fact that an outwardly directed longitudinal seam does not, per se, define an effective stiffening of the container, such a seam is subject to external influences which can easily result in damage. In addition, a longitudinal seam which projects beyond the crosssection of the container will prevent a side-by-side stacking, without leaving spaces or gaps between the containers. It has also been determined that in the course of individual handling of the containers, especially in 3,197,1l2 Patented July 27, 1965 the shipping of filled containers in storage cartons or boxes, it is practically impossible to pick up and deposit the containers without rather severe handling. This handling tends to increase the pressure of the liquid within the container, and the same has a peeling effect which tends to loosen the longitudinal seam, and needless to say,'such loosening of the seam can leadrto leakage.

According to the present invention it is proposed, in connection with a liquid-tight substantially rectangular or prismatic or polygonal container of paper, cardboard and like carton-forming material having its upper and lower ends provided with roof-like folding closures with inwardly folded gable surfaces, to provide such containers with three-layer reinforcing ribs at diagonally opposite edges of the body of the container, with such ribs which are produced by folding and sealing of the walls of the container defining an effective reinforcement of the container, which reinforcement is augmented substantially by virtue of the fact that the ends of the ribs are joined with the ends of the upper and lower roof-like folding closures with inwardly folded gable surfaces, thereby forming what might be termed a reinforcing frame enclosing the container. 7

Furthermore, according to the invention, one of the reinforcing ribs embodies the longitudinal seam of the tubular shaped container body, while the reinforcing rib located diagonally opposite is formed solely by the folding and sealing of the walls of the container body in the zone or area of the edge of the body.

In accordance with the'invention, the reinforcing rib is produced by providing a first leg on one wall of the container body which extends towards the interior of the body, and a second leg which extends towards the exterior of the body, and which second legoverlies the first leg to form a substantially V-shaped fold, with the respective legs being secured together and with the second leg being sealed to the inside of the adjoining wall of the container body.

More specifically, according to the invention, the connection or seal between the first and second legs and between the second leg and the inside of the adjoining wall of the body is such that if a predetermined pressure within the container body is exceeded, the connection or seal between the first and second legs is broken, thus allowing the V-shaped fold to expand without breaking the seal between the second leg and the adjoining wall of the body. 7

By virtue of the foregoing arrangement, it will be appreciated that there is no danger of the longitudinal seam between the second leg of the reinforcing rib 'and the adjoining wall of the body becoming loosened, due to improper handling of the filled container, as previously mentioned, since the pressure is exerted on the first leg of the rib, and thus cannot affect adversely the adhesive zone of the longitudinal seam. Hence, when such pressure conditions arise, the V-shapedfold tends to expand.

Further objects and advantages of the invention will be come more readily apparent from the following detailed description and annexed drawings, and in which drawings:

FIG. 1 is a view in perspective of a closed container constructed in accordance with the present invention;

FIGS. 24 are views in perspective, illustrating the essential forming steps in the production of the container;

FIG. 5 is a cross-sectional View of a container body constructed in accordance with the present invention;

FIG. 6 is a fragmental sectional view on an enlarged scale, illustrating the details of the reinforcing rib, and,

FIG. 7 is a view generally similar to FIG. 5, showing a modified type of container. I

Referring to the drawings, and more particularly to FIG. 1, container C is of prismatic or polygonal form,

and in order to produce the container, there is employed a blank of paper, thin-walled cardboard or other cartonforming material, preferably coated on one side or face or both sides or faces with a thermoplastic synthetic material. This coating not only possesses an impregnating property, but also the property of becoming adhesive, once subjected to pressure and heat. The flat blank thus treated is formed with score or fold lines, so that upon folding and adhesion of a longitudinal seam, a tubular container body which is initially flat is provided.

The container body includes parallel side walls 7, 8 and end walls 11, 12, with the upper and lower ends of the container being closed by means of folding closures 1 and 2,respectively. While the upper closure 1.is of roof-gable type, the lower closure 2 is flat in order to provide a base for permitting the container to stand in an upright position. After the initial'step of folding and providing the longitudinal seam, the container body is erected to its full opened cross-section, as shown in FIG. 2, after which the components of the lower closure 2 are closed, and seam 3 of the closure is laid flat, as best illustrated in FIGS. 1 and 3. After the container C has been filled with liquid or other material, the components of upper closure 1 are closed, and the same is provided with seam 4.

As previously pointed out, the essential feature of the present invention is the provision of reinforcing ribs located at diagonally opposite edges of the container, and such ribs are denoted generally 5 and 6 (FIG. 5). The details of the rib 5 are best shown in FIG. 6, wherein it will be noted that side wall 7 is provided with a first leg 9, which extends towards the interior of the container body, and a second leg 10 which extends towards the exterior of the body with the leg 10 overlying the leg 9, and having its free edge terminating in the plane of the 7 side wall 7. In other words, the legs 9 and 10 provide a substantially V-shaped fold. The end wall 11 overlies the outer face or surface of the leg 10, and the free edge of the wall 11 also lies in the plane of the free edge of the leg 10 and the side wall 7. The outer face or surface of the leg 10 and the inside of the end wall 11 are connected by means of an adhesive or by sealing, and in a similar fashion the opposing faces of the legs 9 and 10 are connected. Thus, the reinforcing rib '5 consists of three layers, and the adhesive or sealing force between such interconnected layers is so selected that in the event of the pressure within the filled containers exceeding a predetermined degree, the connection between the legs 9 and 10 is broken, whereby the V-shaped fold expands without breaking the connection between the leg 10 and the wall '11 which provides the longitudinal seam of the container body C.

The reinforcing rib 6 is generally similar to that of the rib 5, with the exceptionthat the free edge of the leg 10 joins or isintegral with the end wall 12.

In the modification of the container shown in FIG. 7, it will be noted that side walls 7, 8' are inclined in the direction of the container C to the plane defined by the adjacent outer edges of the container body, starting from one edge of the container body. In this embodiment, the leg 9' is of lesser length than the leg 10', and the outer edges of the legs 10 and Walls 11', 12 fall within a plane defined by the outer edges of the seams, and the other edge of the respective end walls.

The invention is not to be confined to any strict conformity to the showings in the drawings, but changes or modifications may be made therein, so long as such changes or modifications mark no material departure from the spirit and scope of the appended claims.

What I claim is:

1. A liquid-tight container including a polygonal body having side walls with opposite edges, end walls with opposite edges and closed ends, one edge of one of said side walls having an inturned leg and an outturned leg, one edge of one of said end walls being attached to the outer face of said outturned leg for producing a longitudinally extending reinforcing rib of three layers, the other of said side walls having one edge thereof provided with an inturned leg and an outturned leg diagonally opposite said first named inturned and outturned legs, one edge of the other of said end walls being attached to the outer face of said last mentioned outturned leg for providing a longitudinally extending reinforcing rib of three layers, the opposite edge of each of said side and end walls being directly joined to provide a single layer therealong, and means defining a seam extending axially of each closed end which merge with said diagonally opposite longitudinally extending ribs for producing a stiffening frame enclosing said container.

2. The liquid-tight container as claimed in claim 1 in which the opposed faces of said inturned and outturned legs are attached together so that if a predetermined pressure within the body is exceeded, the attachment between said faces is destroyed thus allowing the legs to expand without breaking the attachment between the outturned legs and the end walls.

3. The liquid-tight container as claimed in claim 2 in which the end of each outturned leg and said one edge of each wall fall in the same plane as the associated end wall.

4. The liquid-tight container as claimed in claim 1 in which said inturned and outturned legs are of the same length.

5. The liquid-tight container as claimed in claim 1 in which each side wall is inclined throughout its length toward the interior of the body relative to the plane defined by the outer edge of the reinforcing rib and the opposite edge of the side wall with the inturned leg being of lesser length than the outturned leg.

References Cited by the Examiner UNITED STATES PATENTS 2,573,524 10/5 1 Weisberg et a1. 22937 2,577,305 12/51 Brooks 22937 2,594,156 4/52 Guyer 22917 2,792,166 5/57 Brooks 22937 3,120,333 2/64 Seiple 22937 3,124,294 3/64 Zerlin;

FOREIGN PATENTS 558,784 4/ 60 Belgium.

JOSEPH R. LE CLAIR, Primary Examiner.

GEORGE O. RALSTON, Examiner. 

1. A LIQUID-TIGHT CONTAINER INCLUDING A POLYGONAL BODY HAVING SIDE WALLS WITH OPPOSITE EDGES, END WALLS WITH OPPOSITE EDGES AND CLOSED ENDS, ONE EDGE OF ONE OF SAID SIDE WALLS HAVING AN INTURNED LEG AND AN OUTTURNED LEG, ONE EDGE OF ONE OF SAID END WALLS BEING ATTACHED TO THE OUTER FACE OF SAID OUTTURNED LEG FOR PRODUCING A LONGITUDINALLY EXTENDING REINFORCING RIB OF THREE LAYERS, THE OTHER OF SAID SIDE WALLS HAVING ONE EDGE THEREOF PROVIDED WITH AN INTURNED LEG AND AN OUTTURNED LEG DIAGONALLY OPPOSITE SAID FIRST NAMED INTURNED AND OUTTURNED LEGS, ONE EDGE OF THE OTHER OF SAID END WALLS BEING ATTACHED TO THE OUTER FACE OF SAID LAST MENTIONED OUTTURNED LEG FOR 